/**
 * Generate a long shadow effect like [this](https://www.google.ch/search?q=long+shadow&espv=2&biw=2560&bih=1316&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjjne6x49LPAhVBHRQKHat8AW8Q_AUIBigB)
 *
 * @param 		{Color} 		[$color=rgba(0,0,0,.3)] 			The shadow color
 * @param 		{String} 		[$type=text] 						The shadow type (text,box)
 * @param 		{Degree} 		[$angle=135deg] 					The shadow angle
 * @param 		{Integer} 		[$depth=20] 						The shadow depth
 * @param 		{Boolean} 		[$fade=false] 						If true, the shadow will fade itself
 * @param 		{Number} 		[$blur=0] 							The blur amount of the shadow
 * @param 		{Number} 		[$blur-ratio=0] 					The ratio to blur each depth more
 *
 * @example
 * .my-cool-title {
 * 		\@include s-long-shadow(
 * 			$depth : 10
 * 		);
 * }
 * .my-cool-box {
 * 		\@include s-long-shadow(
 * 			$type : box
 * 		);
 * }
 *
 * @author 			Olivier Bossel <olivier.bossel@gmail.com> (https://olivierbossel.com)
 */
@mixin s-long-shadow(
  $color: rgba(0, 0, 0, 0.3),
  $type: text,
  $angle: 135deg,
  $depth: 20,
  $fade: false,
  $blur: 0,
  $blur-ratio: 0
) {
  @if $_sugar-test-arguments {
    $color: s-test-argument("s-long-shadow", "color", color, $color);
    $type: s-test-argument("s-long-shadow", "type", (text, box), $type);
    $angle: s-test-argument("s-long-shadow", "angle", degree, $angle);
    $depth: s-test-argument("s-long-shadow", "depth", integer, $depth);
    $fade: s-test-argument("s-long-shadow", "fade", boolean, $fade);
    $blur: s-test-argument("s-long-shadow", "blur", number, $blur);
    $blur-ratio: s-test-argument(
      "s-long-shadow",
      "blur-ratio",
      number,
      $blur-ratio
    );
  }

  $angle: (s-strip-units($angle) - 90);
  $x: 1.5 * cos($angle) + 0px;
  $y: 1.5 * sin($angle) + 0px;
  $darken: (lightness($color) / $depth)/2;
  $opacify: 0;
  $shadow: ();

  $darken: 0;

  @if $fade == true {
    $opacify: (opacity($color) / $depth);
    transform: translateX(0);
  }

  @for $i from 1 through $depth {
    $b: $blur;
    @if $blur-ratio > 0 {
      $b: $blur + $i * $blur-ratio;
    }
    $shadow: $shadow,
      $i *
        $x
        $i *
        $y
        $b
        hsla(
          hue($color),
          saturation($color),
          (lightness($color) - ($i * $darken)),
          1 - ($i * $opacify)
        );
  }
  #{$type}-shadow: $shadow;
}